Mobile haul vehicles, such as mining trucks and articulated haul trucks (hereinafter referred to as “haulers”), have historically been used to transport minerals or other materials between different locations at a worksite and from a worksite to other locations. For example, the haulers can be loaded with ore at a first location by an excavation machine (e.g., a rope shovel, a hydraulic shovel, a front end loader, or other excavators—hereinafter referred to as “loaders”), and transport the ore to a processor at a second location at or away from the worksite. When a hauler such as a dump truck is loaded with ore or other materials at the worksite, uneven truck payload distribution causes uneven tire loading and excessive tire heating. This can reduce productivity as truck speeds are reduced as a result of the higher tire temperatures. Uneven truck payload distribution can also cause excessive wear on mechanical components of the truck.
Improper payload distribution also promotes vehicle wear. Strut, frame, and tire damage can occur if the payload is distributed unevenly. A payload monitor may accurately calculate total payload with an unsymmetrical distribution, but does not fully protect the vehicle frame and suspension from overloads. Merely determining the actual payload to prevent overloading is not sufficient to fully protect the vehicle, since uneven distribution causes overloads on portions of the vehicle. An operator of a loader such as a front end loader or other excavator needs real time indications of the position of the payload on a hauler during the loading process in order to achieve optimal load placement.
One attempt to address the above-identified issues is disclosed in U.S. Pat. No. 4,852,674 of Gudat that issued on Aug. 1, 1989 (“the '674 patent”). In particular, the '674 patent discloses an apparatus for displaying the distribution of the load, in a hauler such as an off-highway truck, to both the hauler operator and the loader operator. The information is conveyed to the operators using displays having varying color ranges generally indicative of the load in portions of the dump body of the hauler. Using this tool the hauler operator attains optimum positioning of the hauler prior to and during the loading cycle, while the loader operator directs loads to portions of the dump body of the hauler having lower displayed loads.
Although the apparatus of the '674 patent helps a loader operator to evenly distribute the payload on a hauler in real time, further improvements may be achieved by providing the loader operator with additional real time information during a loading process. Examples of useful additional information may include providing the loader operator with a visual indication of exactly where the center of gravity of the total payload of material on a hauler is located before and after each load is deposited on the hauler, and a visual indication of how the loader itself is positioned relative to the orientation of the hauler each time the hauler is moved into position relative to the loader for receipt of another load. A loader operator may have a limited field of view when approaching a hauler or when a hauler is maneuvered into position near the loader, and while the loader is carrying a load of material to be dumped onto the hauler. More than one hauler may also be moved into position on opposite sides of a loader during a loading operation, thereby requiring a loader operator to have a different perspective while loading each of the haulers. A relatively inexpensive and portable, stand-alone system that can be provided on demand to a loader operator if desired, and display all of the above information in real time, would facilitate optimal loading for increasing the longevity of tires and other operational components of the haulers.
The load position indicating system and load position display indicator according to the present disclosure are directed towards overcoming one or more of the problems set forth above and/or other problems of the prior art.